HARTFORD, Conn. (AP) -- Some letters come from church groups, others from parents who've lost children of their own. One came from a police officer who responded to the bombing of the federal building in Oklahoma City.

They're some of the estimated 175,000 cards and letters of support and condolences that have poured into Newtown from around the world since December's massacre at Sandy Hook Elementary school, and volunteers are working to preserve them and say thank you to as many senders as they can, one handwritten note at a time.

The archiving project is the brainchild of resident Yolie Moreno, who said she was floored to see the trays and trays of letters lining the walls of the town's municipal building after the mass shooting, many containing artwork or the thoughts of schoolchildren.

One that touched her was a child's watercolor painting, with "You don't know how strong you are until being STRONG is the only option you have," written over it in marker.

"It's incredible, incredible stuff," Moreno said. "And I imagine everyone who sent something would like to know that it was held, read, touched, photographed and shared."

With the permission of town officials, Moreno and a handful of other volunteers have begun photographing as much of it as they can.

"Tray by tray, we'd take the letters out of the envelopes and photograph them, sometimes as a group, sometimes single letters, and try to motor through as much as we could," Moreno said.

The letters were boxed this week and taken to a storage unit, where Moreno and her team will continue to have access to them. Once they are archived, the plan is to incinerate the items and use the ashes to help create concrete for whatever memorial to the shooting victims is built, she said.

Moreno said it's not clear what will be done with the digital photographs. She would like to create a website where the public could view them.

One side benefit, she said, is the group has found checks or other gifts in the mail that were overlooked earlier. Those were given to the town or charities to which they are addressed.

Meanwhile, another group, the Newtown Volunteer Task Force, has begun answering some of that mail.

The organization, which is coordinating all the volunteer work being done for Newtown, created thank-you cards that read in part, "Your voice has been heard and your caring is deeply appreciated."

Under that printed message, a volunteer includes one or two handwritten lines to let the recipient know that their letter was read.

Volunteers are going through letters and picking out ones that touch them personally, said Robin Fitzgerald, a task force organizer.

Because the task force has no budget, the volunteers are asked to bring their own stamps.

Renee Berger, 60, lives in neighboring Monroe and volunteers at the center. She says she's answered letters from parents and grandparents who have lost children of their own to cancer or some other tragedy, and many church groups.

"We have a box of tissues on the table because you can't read these letters without reacting," she said.

Fitzgerald acknowledged the group likely will only be able to respond to a fraction of the correspondence but said the project is open-ended, and the more volunteers the group gets, the more thank-you notes it will be able to write.